Fluid sampling device



May 1, 1962 c. R. STRUCK FLUID SAMPLING DEVICE '3 Sheets-Sheet 1 Filed Nov. 25, 1960 2 M 2 I I 6 6 2 mm M. a \i m I M I? M 2 1 3 Q 6 M 6 n 6 w P [men-roe Cannes R. STRUCK M Arm May 1, 1962 c. R. STRUCK FLUID SAMPLING DEVICE 5 Sheets-Sheet 2 Filed Nov. 25, 1960 INvaN'roR CHARLES R. Srnuuq M I M ATTY- May 1, 1962 c. R. STRUCK 3,031,890

FLUID SAMPLING DEVICE Filed Nov. 25, 1960 3 Sheets-Sheet 3 l 1 ,m'l

taes

The present invention relates to fluid sampling devices for separating'small representative quantities or samples of a fluid from a flow line of such fluid. The invention has particular reference to fluid sampling devices of the type shown and described in my prior United States Patent No. 2,784,594, granted on March 12, 1957, and entitled Fluid Sampling Device, over which device the present one is an improvement.

Briefly, the fluid sampling device of my prior patent is in the form of a self-contained unit adapted to be interposed in a fluid line as, for example, a sectional fluid conduit, and having associated therewith a fluid chamber within which an operating plunger reciprocates. The fluid chamber exists by virtue of a rotatable carrier and sleeve assembly, the plunger and sleeve thereof having associated therewith cooperating porting by means of which fluid is intermittently introduced into the fluid chamber for immediate and subsequent discharge therefrom by an operative stroke of the plunger. The carrier is rotatable within the sleeve to effect proper timing of the porting arrangement, as well as to effect proper timing of the plunger stroke, the latter being effected by fluid pressure operating upon one end of the plunger. The plunger is yieldingly maintained in its retracted position under the influence of a spring. Rotation of the carrier in the stationary sleeve, serves, through the cooperating porting, to control the intermittent admission of fluid to the chamber and also to control the proper application of fluid pressure selectively to the opposite ends of the plunger to control the movements of the latter in timed relation to the introduction of fluid to the chamber. The carrier is adapted to be continuously rotated under the motivating influence of fluid passing through the fluid line, a turbine action utilizing turbine vanes on the car rier being employed for this purpose.

Fluid sampling devices constructed in accordance with the principles briefly outlined above, as exemplified by my prior patent above referred to, are possessed of certain limitations, principal among which is the fact that rotation of the carrier is dependent upon the rate of flow of fluid through the fluid line. Where low pressures, and consequently low rates of flow of the fluid are involved, insufficient pressure on the turbine vanes may cause stalling of the turbine mechanism. Such a condition is apt to be prevalent under conditions of high fluid viscosity, high fluid density, low temperatures, the presence of solid material in the fluid, and other factors. Furthermore, conditions involving the above mentioned factors, as well as surface tension, adhesive qualities of the fluid, and other factors, may cause erratic operation of the carrier.

The present invention is designed to overcome the above-noted limitations that are attendant upon my prior fluid sampling device and, toward this end, the present invention contemplates the provision of a fluid sampling device which, in the main, operates upon the same general principles as that of my prior device, but in which the sleeve, instead of the carrier, is rotated to effect the necessary relative movement between the sleeve and carrier. By thus rotating the sleeve instead of the carrier, a very material simplification in the structure involving an appreciable reduction in the number of moving parts involved, is attained. Another and equally important feature of the present invention resides in the elimination of a turbine drive. According tothe present invention,

there has been substituted for such drive a positive motivation of the sleeve associated with the carrier, such motivation in the illustrated form of the invention operating under the control of an electric motor.

Still another feature of the present invention which serves to distinguish it from my prior fluid sampling device resides in the provision of a more positive means for controlling the movements of the fluid-ejecting plunger, this means assuming the form of a cam which exerts a positive action upon the plunger to restore it to its retracted position rather than relying upon yieldable spring means for effecting this function.

Yet another feature of the invention, in an apparatus of this sort, is to provide a novel means for effecting a scavenging action of the sample containing fluid chamber after each fluid sample has been expelled from the latter.

The provision of a fluid sampling device which is relatively simple in its construction, and which, therefore, may be manufactured at a relatively low cost; one which is comprised of a minimum number of parts, particularly moving parts, and which, therefore, is unlikely to get out of order; one which is rugged and durable and which, therefore, will effectively serve its intended purpose over a long period of time Without requiring servicing; one in which the operative moving parts thereof have extremely low torque requirements; one which will operate to entrain for discharge purposes a relatively large number of fluid samplings over a given period of time; one which will withdraw the samples from a region of an average consistency; one which will deliver the entire portion of each fluid sample to the fluid receptacle; one which will effect such delivery of the samples to the receptacle immediately after their entrainment; one in which the accumulation of fluid in the sample lines is avoided; one which is smooth and silent in its operation; and one which, otherwise, is a well-adapted to perform the services required of it, are further desirable features which have been borne in mind in the production and develop ment of the present invention.

Numerous other objects and advantages of the invention, not at this time enumerated, will become more readily apparent as the following description ensues.

In the accompanying three sheets of drawings forming a part of this specification, one illustrative embodiment of the invention has been shown.

In these drawings: FIG. 1 is a side elevational view of a fluid samplin device constructed in accordance with the principles of the present invention and showing the same operatively installed in a fluid line;

FIG. 2 is an enlarged sectional view taken substantially vertically and centrally through the fluid sampling device of FIG. 1;

FIG. 3 is an exploded perspective viewshowing the component parts of the fluid sampling device and illustrating their positional relationship relative to one another;

FIG. 4 is a fragmentary sectional view taken substantially along the line 44 of FIG. 2;

FIG. 5 is a sectional view taken substantially along the line 5-5 of FIG. 4;

FIG. 6 is a sectional view similar to FIG. 4 with the various parts in the positions they assume at the end of the first-quarter cycle of the operation of the apparatus;

FIG. 7 is a sectional view taken substantially along the line 77 of FIG. 6;

FIG. 8 is a sectional view similar to FIG. 4 showing the parts in the positions which they assume at the end of one-half cycle of the operation of the apparatus;

FIG. 9 is a sectional view taken substantially along the line 9--9 of FIG. 8;

FIG. 10 is a sectional view similar to FIG. 4 showing the parts in the positions which they assume at the end 3 of the third-quarter cycle of operation of the apparatus; and

FIG. 11 is a sectional view taken substantially along the line 11-11 of FIG. 10.

Referring now to the drawings in detail and in particular to FIG. 1, the invention has been shown in an environment wherein the same is interposed in a fluid stream passing through a fluid line including pipe sections and 12. The fluid sampling device has been designated in its entirety at 14 and it includes an outer casing 16 having an inlet leg 18 operatively connected to the pipe section 10 and an outlet leg 20 operatively connected to the pipe section 12. Fluid is adapted to be by-passed around the fluid sampling device 14 through a sectional branch conduit 22 having a manually-controlled valve 24 interposed therein. A pair of shut-off valves 26 and 28 are disposed in the conduit sections 10 and 12, respectively, on opposite sides of the device 14 so that when these two latter valves are closed and the valve 24 is opened, fluid will pass directly from the pipe section 10 to the pipe section 12. When the valve 24 is closed and the valves 26 and 28 are opened, fluid will pass through the fluid sampling device 14.

A bracket assembly 30 is operatively mounted on the pipe section 12 and serves to support thereon a receptacle 32 in which relatively small samples of fluid withdrawn from the casing 16 in a manner that will be made clear presently are collected. The bracket assembly 30 also serves to support an electric motor M by means of which the operative parts of the fluid sampling device 14 are positively driven.

Referring now to FIGS. 2 and 3, the casing 16 per se is in the form of a T having the aforementioned inlet and outlet legs 18 and 20 and a third leg 34, this latter leg being threaded interiorly as at 36 for threaded reception therein of a bushing 40. The bushing 40 is generally'of cup-shaped design and is provided with an end wall 42 having an opening 44 through which there projects one end of a nonrotatable cage member 46. The cage member 46 is generally of tubular design and it is provided with an end flange 48. A resilient O-ring St is interposed between the end flange 48 and end wall 42 of the bushing 40, while a follower 52, which is telescopically received within the bushing 40 and which is adapted to be clamped thereto by means of a series of clamping bolts 54, bears against the flanged end of the cage 46 and serves to compress the O-ring against the end wall 42 to thus effect a fluid seal between the parts.

Thecage member 46 projects through the opening 44 and extends axially across the casing 16 to a region adjacent the forward end thereof so that it is thus positioned directly in the fluid stream passing through the casing 16 from the inlet leg 18 to the outletleg 20 thereof. The tubular cage member is formed with an internal annular flange 56 which, in combination with a packing nut 58, defines a packing gland within which there is contained a quantity of a suitable packing material 60*. An elongated tubular drive shaft 62 having a bore 63 therein projects through the packing gland, and the forward end of the drive shaft has integrally formed thereon a composite sleeve member including a sleeve proper 64, the nature and function of which will be made clear presently. The sleeve proper 64 is loosely disposed and it rotates within;t he cage member 46. A washer 65 is interposed between the rear end of the sleeve and the flange 56.

The drive shaft 62 projects through a delivery fitting 66 and has its rear end operatively connected by means of a coupling 68 to the drive shaft 70 of the electric motor M.

The delivery fitting 66 includes an upper horizontal sleeve portion 72 and a lower vertical delivery tube proper 74, the lower end of the latter communicating with the interior of the receptacle 32. .A pair of bearing assemblies 76 associated with the sleeve portion 72 of the delivery fitting 66 serves rotatably to support the medial region of the drive shaft 62. A plurality of ports 78 are formed in the wall of the drive shaft in communication with the interior of the delivery tube 74.

Still referring to FIGS. 2 and 3, the tubular cage member 46 is formed with a pair of upper and lower diametrically opposed slots 30 and 82, respectively, which permit free flow of fluid around the member 64. A cupshaped liner which may be formed of a suitable plastic material is disposed within the sleeve proper 64 with a tight fit, is rotatable in unison with the sleeve 64 and is provided with a relatively thin, cylindrical wall portion 92 and a relatively thick radial end wall 94. The cylindrical wall portion 92 is provided with a pair of holes 96 and 98 therein in permanent register with the ports 84 and 86, respectively, these holes serving merely as extensions of the ports.

A floating carrier 100, including an enlarged cylindrical body portion 102 and a reduced stern portion 104, is slidably disposed Within the liner 90 and is normally urged rearwardly within the latter by means of a helical coil spring 106 which bears at its forward end against a snap ring 168 carried near the forward open end of the cage member 46, and at its other end against a forwardly facing shoulder 110 provided on the carrier. The body portion 162 is provided with a frusto-conical face 112 de signed for yielding engagement with a complementary frusto-conical face 114 provided on the thickened wall portion 92 of the liner 90, these two frusto-conical surfaces being maintained in yielding contact by means of the spring 166. I

The carrier 100 is held against rotation within the liner 90 by means of a pin 116 which projects through a narrow extension 11% of the upper slot 80 provided in the cage member 46 and which extends into the body portion 102 of the carrier 100.

The body portion 102 of the carrier 164i is formed with an elongated vertical slot 120 therethrough. The sleeve 64 is rotatably disposed within the annulus existing between the carrier and the cage member. The two ports 84 and 86 provided in the sleeve upon rotation of the latter serve to effect intermittent admission of small quantities of fluid passing through the casing 16 to the interior of the slot 1211, as Well as to effect an automatic cut-off whereby such fluid as has entered the slot 120 will be entrapped therein for subsequent expulsion therefrom under the motivating influence of a plunger 122, which is slidably disposed within the slot, and the movements of which are controlled by mechanism subsequently to be described.

The liner 90 is provided with a longitudinally extending port 124, this port being disposed in the peripheral regions of the liner end wall 94. A cooperating port 126 provided in the rear end of the carrier repeatedly communicates in passing with the upper portion of the slot 120 during rotation of the sleeve 64 and its liner 9!).

The plunger 122 is in the form of a flat, generally rectangular, block-like body having oppositely facing lateral extensions or fingers 128 at the forward end thereof. The transverse cross-sectional area of the plunger 122 is substantially equal to the transverse cross sectional area of the slot 121 so that the plunger may operate in the manner of a piston within the slot and be impelled rearwardly in the slot under the motivating influence of fluid admitted under pressure to the forward end of the slot to drive the plungerrearwardly within the latter.

As bestsee n in FlG. 3, the rear rim of the sleeve 64 is shaped to provide a pair of cam edges 130, including dropoff portions 132, these cam edges being designed for camming engagement with the protuberances 128 for the purpose of returning the plunger 122 to its retracted position after each forward fluid-discharging stroke thereof. The operative stroke of the plunger 122 is effected under the motivating influence of fluid pressure acting upon the forward end face 134 of the plunger. This forward end face of the plunger 122 is of an obtuse angular configuration to provide clearance regions so that fluid may enter between the end face of the plunger and the adj cent vertical end wall of the slot 120 preparatory to the operative stroke of the plunger.

In the operation of the device, when the same is operatively installed in a fluid pressure line, as illustrated in FIG. 1, with the valve 24 closed and the two valves 26 and 28 open, a substantially steady stream of fluid will flow from the pipe section through the casing 16 to the pipe section 12. Assuming the motor M to be energized, the sleeve 64 which is carried at the forward end of the rotating drive shaft 62 will be caused to rotate Within the annulus existing between the cage member 46 and the body portion 102 of the carrier 100. Assuming that, at the commencement of each sampling cycle, the diametrically opposed ports 84 and 86 in the leeve 64 are in register with the elongated slots '80 and 82, respectively, in the cage member 46, fluid will pass through these registering slots and ports and fill the vertically disposed slot 120 provided in the body portion 102 of the carrier 10% At this time, the two lateral extensions or fingers 128 provided on the plunger 122 will bear against the high portions of the cam edges 130 provided on the rear rim of the sleeve 64 so that the plunger will be held in its retracted position, such a position of the parts being illustrated in FIGS. 4 and 5. Also, at this time, the longitudinally extending port 124 provided in the thickened end wall 94 of the liner 90 will be'out of register with the longitudinallyextending port 126 formed in the rear region of the carrier 100. Upon continued rotation of the sleeve 64 in the direction indicated by the arrow in FIG. 4 .the ports 84 and 86 in the sleeve 64 will move out of register with the vertical slot 120 inthe carrier 1% so that an imperforate portion of the sleeve 64 will close the upper and lower ends of this latter slot 120 and entrap'a quantity of the fluid within the slot.

After the sleeve has rotated throughout an angle of 90 in the direction indicated by the arrow in FIG. 4, thus completing the first-quarter cycle of the operation of the apparatus, the port 126 in the carrier 100 will move into register with the port 124 in the end wall 92 of the liner 90 as shown in FIGS. 6 and 7, thus establishing communication through these two registering orts between the bore 63 of the drive shaft and the vertical slot 120 of the carrier 100. Immediately prior to movement of the sleeve 64 to its quarter-cycle position, the two fingers 128 on the plunger 122 encounter the dropofl portions 132 of the cam edges 139, whereupon fluid pressure exerted upon the obtuse end face 134 of the plunger 122 will drive the plunger rearwardly within the slot 120 and cause the fluid entrapped in the latter to be expelled through the two registering ports 126 and 124. This expelled fluid will enter the elongated central bore or passage 63 provided in the drive shaft 62 and from thence it will pass along the bore 63, through the ports or holes 78, and through the vertical discharge tube 74 from whence it will enter the receptacle 32.

As the sleeve 64 continues to rotate, the ports 84 and 86 will remainout of register with the vertical slot 120 in the carrier 16%) so that the vertical slot 120 remains out of fluid contact with the surrounding fluid in the casing 16. As thesleeve 64 approaches its 180 position at the half-cycle of the-operation of the device, the. slots 84 and 86 will again move into vertical register with the slot 120 in the carrier 100 as shown in FIGS. 8 and 9 and thus cause this latter slot to become scavenged by passage of fluidfrom the upstream side of the fluid stream directly through the port 86in the sleeve 64, slot 120 in the carrier 160, port 84 in the sleeve 64, in the order named and in straight-line fashion. 4

Continued rotation of the sleeve 64 will cause the ports 84 and 86 to move out of register with the slot 120, thus entrapping a quantity of fluid in this latter slot. In the three-quarter cycle position of the parts wherein the sleeve 64 has been rotated about an angle of 270, the

two ports 124 and 126 will remain out of register with each other as shown in FIG. 10, while at the same time communication of the ports 84 and 86 with the slot 120 will be effectively prevented by an imperforate portion of the sleeve 64. The fluid entrapped within the slot 120 remains within the slot until the cycle has been completed and the sleeve 64 has beenrotated throughout 360 so that the parts again assume the position shown in FIGS. 4 and 5. At this time, the entrapped fluid within the slot 120 will be replaced by a fresh sample of fluid in the manner previously described and the cycle will be repeated.

From the above description, it is throught that the construction, operation and many advantages of the herein described fluid sampling device will be readily apparent. The invention is not to be limited to the exact arrangement of parts shown in the accompanying drawings or described in this specification as various changes in the details of construction may be resorted to without departing from the spirit of the invention. Only insofar as the invention has particularly been pointed out in the accompanying claims is the same to be limited.

Having thus described the invention What I claim as new and desire to secure by Letters Patent is:

l. A sampling device for fluid under pressure in a flow line, comprising: a casing provided with a fluid inlet and a fluid outlet, a generally cylindrical cage member nonrotatively mounted with the casing and projecting into said flow line, a sleeve member mounted for rotation and fitting within said cage member, a hollow rotatable drive shaft through which samples of fluid are adapted to be expelled firom the casing projecting into said casing and connected to said sleeve member in driving relationship, a carrier fitting within said sleeve member and provided with a chamber therein, interengaging means on the cage member and carrier for preventing rotation of the latter, means controlled by rotation of the sleeve member for conducting fluid from the chamber to the hollow drive shaft, the carrier and sleeve member being provided with coacting means responsive .to the rotation of the sleeve member for successively admitting samples of fluid into the chamber and trapping the same in the latter, a plunger slidable in the carrier for expelling the trapped samples from the chamber into the hollow drive shaft, and means for imparting expelling strokes to the plunger.

2. A'sampling device for fluid under pressure in a flow line, comprising: a casing provided with a fluid inlet and a fluid outlet, a generally cylindrical cage member non rotatively mounted within the casing and projecting into.- the flow line, a sleeve member mounted for rotation and with said ports and responsive to the rotation of the,

sleeve member for successively admitting samples of fluid into the chamber and trapping the same in the latter, a plunger fitting in the chamber in the carrier, and means operable by fluid pressure for imparting expelling strokes to the plunger. i

. 3. A sampling device for fluid under pressure in a flow line, comprising: a generally cylindrical cage member nonrotatively mounted within the casing and projecting into the flow line, a sleeve member mounted for rotation and fitting within said cage member, said sleeve member being provided with diametrically opposed ports, a hollow rotatable drive shaft through which samples of fluid are adapted to be expelled from the casing projecting into the casing and connected to the sleeve member in driving relationship, a carrier fitting within said sleeve member and having a diametrically extending slot therein, interengaging means on the cage member and carrier for preventing'rotation of the latter, means controlled by the sleeve member for conducting fluid from the chamber to the hollow drive shaft, the carrier having means coacting with said ports and responsive to the rotation of the sleeve member for successively'admi-tting samples of fluid into the chamber and trapping the same in the latter, a plunger fitting in the chamber in the carrier for expelling samples from the chamber into the hollow drive shaft, fluid pressure means for imparting expelling strokes to the plunger, and interengaging cam means on said sleeve member and plunger for retracting the latter.

4. A sampling device for fluid under pressure in a flow line, comprising: a generally cylindrical cage member nonrotatively mounted within the casing and projecting into the flow line, a sleeve member mounted for rotation and fitting within said cage member, said sleeve member being provided with diametrically opposed ports, a hollow rotatable drive shafit through which samples of fluid are adapted to be expelled from the casing projecting into the casing and connected to the sleeve member in driving relationship, a carrier fitting within said sleeve member and having a diametrically extending slot therein, interengagin g means on the cage member and carrier for preventing rotation of the latter, mean-s controlled by the sleeve member for conducting fluid from the chamber to the hollow drive shaft, the carrier having means coacting with said ports and responsive to the rotation of the sleeve member for successively admitting samples of fiuid into the chamber and trapping the same in the latter, a plunger fitting in the chamber in the carrier for expelling samples from the chamber into the hollow drive shaft,fluid pressure means for imparting expelling strokes to the plunger, interengagin'g cam means on said sleeve member and plunger for retracting the latter, and means controlled by the sleeve member and operable after each expelling stroke of the plunger for passing a quantity of fluid completely through the chamber toscavenge the latter. I

5. A sampling device for fluid under pressure in a flow line, comprising: a casing provided with a fluid inlet and a fluid outlet, a generally cylindrical cage member nonrotatively mounted within the casing and projecting into said flow line, a sleeve membermounvted for rotation and fitting within said cage member, a hollow rotatable drive shaft through which samples of fluid are adapted to be expelled from the casing projecting into said casing and connected to said sleeve member in driving relationship, a carrier-fitting within said sleeve member and provided with a chamber therein, interengaging means on the cage member and carrier for preventing rotation of the latter, means con-trolled by rotation of the sleeve member for conducting fluid from the chamber to the hollow drive shaft, the carrier and sleeve member being provided with coactin-g means responsive to the rotation of the sleeve member for successively admitting samples of fluid into the chamber and trapping the same in the latter, a plunger slidable in the carrier for expelling the trapped samples from the chamber into the hollow drive shaft, means for imparting expelling strokes to the plunger, and means controlled by rotation of the sleeve member and operable after each expelling stroke of the plunger for passing a quantity of fluid completely thrdugh the chamber to scavenge the latter.

6. A sampling device for fluid under pressure in a flow line, comprising: a generally cylindrical cage member nonrotatively mounted within the casing and-projecting into the flow line, a sleeve member mounted for rotation and fitting within said cage member, said sleeve member being provided with diametrically opposed ports, a hollow rotatable drive shaft through which samples of fluid are adapted to be expelled from the casing projecting into the casing and connected to the sleeve member in driving relationship, a carrier fitting within said sleeve member and having a diametrically extending slot therein, interengaging means on the cage member and carrier for preventing rotation of the latter, means defining a diametrically extending slot in the carrier, the ends of which are movable into register with the ports in the sleeve member during each 180 rotation of the sleeve member, said sleeve member being provided with a longitudinally extending port for establishing communication between the hollow drive shaft and the interior of the sleeve member, said carrier being provided with a cooperating longitudinally extending port designed for registry with said longitudinally extending port in the sleeve member and, when in such registry, establishing communication between said slot and the hollow drive shaft, said longitudinally extending ports being designed for registry with each other during each 360 rotation of the sleeve member and at a time when said ends of the slot in the carrier are out of register with the cooperating ports in the sleeve member, a plunger reciprocable in said slot for expelling samples from the slot through said longitudinally extending ports to the hollow drive shaft, and means for imparting expelling strokes tothe plunger.

7. A sampling device for fluid under pressure in a flow line, comprising: a generally cylindrical cage member nonrotatively mounted within the casing and projecting into the flow line, a sleeve member mounted for rotation and fitting Within said cage member, said sleeve member being provided with diametrically opposed ports, a hollow rotatable drive shaft through which samples of fluid are adapted to be expelled from the casing projecting into the casing and connected to the sleeve member in driving relationship, a carrier fitting within said sleeve member and having a diametrically extending slot therein, interengaging means on the cage member and carrier forpreventing rotation of the latter, means defining a diametrically extending slot inthe carrier, the ends of which are movable into register with the ports in the sleeve member during each 180 rotation of the sleeve member, said sleeve memher being provided with a longitudinally extending port for establishing communication between the hollow drive shaft and the interior of the sleeve member, said carrier eing provided with a cooperating longitudinally extending port designed for registry with said longitudinally extending port in the sleeve member and, whenvin such registry, establishing communication between said slot and the hollow drive shaft, said longitudinally extending ports being designed for registry with each other during each 360 rotation of the sleeve member and at a time when said ends of the slot in the carrier are out of register with the cooperating ports in the sleeve member, a plunger reciprocable in said slot for expelling samples from the slot through said longitudinally extending ports to the hollow drive shaft, means for imparting expelling strokes to the plunger, and interengagingcarn means on the sleeve member and plunger for effcting retraction of said plunger.

8. A sampling device for fluid under pressure in a flow line, comprising: a generally cylindrical cage member nonrotatively mounted within the casing and projecting into the fiow'line, a sleeve member mounted for rotation and fitting within said cage member, :said sleeve member being provided with diametrically opposed ports, a hollow rotatable drive shaft through whichsamples of fluid are adapted to be expelled from the casing projecting into the casing and connected to the sleeve member in driving relationship, a carrier fitting within said sleeve member and having a diametrically extending slot therein, interengaging means on the cage member and carrier for preventing rotation of the latter, means defining a diametrically extending slot in the carrier, the ends of which are movable into register with the ports in the sleeve member during each rotation of the sleeve member, said sleeve member being provided with a longitudinally extending port for establishing communication between the hollow drive shaft and the interior of the sleeve member, said carrier being provided with a cooperating longitudinally extending port designed for registry with said longitudinally extending port in the sleeve member and, when in such registry, establishing communication between said slot and the hollow drive shaft, said longitudinally extending ports being designed for registry with each other during each 360 rotation of the sleeve member and at a time when said ends of the slot in the carrier are out of registry with the cooperating 10 ports in the sleeve member, a plunger reciprocable in said slot for expelling samples from the slot through said longitudinally extending ports to the hollow drive shaft, fluid pressure means for imparting expelling strokes to the plunger, and interengaging cam means on the sleeve member and plunger for eflecting retraction of the plunger.

References Cited in the file of this patent UNITED STATES PATENTS 2,623,544 Waters et a1 Dec. 30, 1952 2,784,594 Struck Mar. 12, 1957 

